The research program of this laboratory centers on the isolation, properties and biological functions of proteins associated with DNA in the chromosomes of higher organisms. Particular emphasis is placed on reactions which modify the structure of histones, HMG proteins, and other nuclear proteins after their synthesis is completed. Reactions such as acetylation of lysine residues, methylation of lysine and arginine residues, and phosphorylation of serine and threonine residues in the intact polypeptide chains of nucleic acid-binding proteins are believed to play an important role in the control of chromatin structure and transcriptional activity. The chemical and enzymatic basis of these reactions, and their consequences in terms of DNA conformational changes and alterations in template function are major topics of investigation.